garrytan/gstack · error · Error

CSS value rejected: contains potentially dangerous pattern.

Error message

CSS value rejected: contains potentially dangerous pattern.

What it means

Error "CSS value rejected: contains potentially dangerous pattern." thrown in garrytan/gstack.

Source

Thrown at browse/src/write-commands.ts:786

        return idx !== undefined ? `Reverted modification #${idx}` : 'Reverted last modification';
      }

      // style <selector> <property> <value>
      const [selector, property, ...valueParts] = args;
      const value = valueParts.join(' ');
      if (!selector || !property || !value) {
        throw new Error('Usage: browse style <sel> <prop> <value> | style --undo [N]');
      }

      // Validate CSS property name
      if (!/^[a-zA-Z-]+$/.test(property)) {
        throw new Error(`Invalid CSS property name: ${property}. Only letters and hyphens allowed.`);
      }

      // Validate CSS value — block data exfiltration patterns
      const DANGEROUS_CSS = /url\s*\(|expression\s*\(|@import|javascript:|data:/i;
      if (DANGEROUS_CSS.test(value)) {
        throw new Error('CSS value rejected: contains potentially dangerous pattern.');
      }

      const mod = await modifyStyle(page, selector, property, value);
      return `Style modified: ${selector} { ${property}: ${mod.oldValue || '(none)'} → ${value} } (${mod.method})`;
    }

    case 'cleanup': {
      // Parse flags
      let doAds = false, doCookies = false, doSticky = false, doSocial = false;
      let doOverlays = false, doClutter = false;
      let doAll = false;

      // Default to --all if no args (most common use case from sidebar button)
      if (args.length === 0) {
        doAll = true;
      }

      for (const arg of args) {

View on GitHub (pinned to 94993f7401)

When it happens

Trigger: Thrown at browse/src/write-commands.ts:786 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of garrytan/gstack@94993f7401 (2026-08-12). Data as JSON: /api/errors/e28194969b8640ea. Report an issue: GitHub.